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Date:   Wed, 10 Apr 2019 10:31:42 -0700
From:   Davidlohr Bueso <dave@stgolabs.net>
To:     Waiman Long <longman@redhat.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Will Deacon <will.deacon@arm.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-kernel@vger.kernel.org, x86@kernel.org,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Tim Chen <tim.c.chen@linux.intel.com>
Subject: Re: [PATCH-tip v2 06/12] locking/rwsem: Wake up almost all readers
 in wait queue
Message-ID: <20190410173142.dt5uldtgt4brhtjj@linux-r8p5>
References: <20190405192115.17416-1-longman@redhat.com>
 <20190405192115.17416-7-longman@redhat.com>
 <20190410165013.njy5bg32pxq6syyr@linux-r8p5>
 <114e3bc3-3b66-4a50-d422-6a477d85fa72@redhat.com>
 <20190410172254.ivgcgehjhqgwjtda@linux-r8p5>
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On Wed, 10 Apr 2019, Bueso wrote:

>On Wed, 10 Apr 2019, Waiman Long wrote:
>>2) I want to avoid the extreme case that there are more than 32k readers
>>in the wait queue and make the count overflow.
>
>But in this case the readers are already on the queue.

Never mind this.

But the limit could still be enlarged just to prevent overflows in the case
where there are only readers.